Enhanced photoluminescence quantum efficiency and stability of water assisted CsPbBr3 perovskite nanocrystals

Abstract Perovskite nanocrystals (NCs) are promising emissive materials for application in light-emitting diodes (LEDs) due to their high quantum efficiency and narrow full width at half maximum (FWHM). However, the ion bonding character of perovskite leads to their quick chemical decomposition under atmospheric moisture. Herein, we present CsPbBr3 perovskite NCs that achieved improved efficiency and stability with the addition of water during the synthesis process. The CsPbBr3 NCs synthesized with a controlled amount of water exhibited a quantum yield greater than 90%, sustained stability over 35 days and a much narrower FWHM than CsPbBr3 NCs that did not use water. Finally, water-added perovskite NC LEDs were fabricated and they showed a nearly 5-times improvement in current efficiency compared to the reference device.